1. Field of the Invention
This invention relates to an automatic page turning-over apparatus for automatically turning over the pages of a book or a plurality of sheets bound like a book by a binder or the like (hereinafter simply referred to as a "book").
The automatic page turning-over apparatus is used, for example, when a number of originals bound like a book are photographed or copied by a flat type camera or a copying apparatus, or when a physically handicapped person reads a book.
2. Related Background Art
Apparatus for automatically turning over the pages of a book are described in Japanese Laid-Open Patent Application No. 60294/1981 and Japanese Laid-Open Patent Application No. 119125/1981.
The apparatus described in Japanese Laid-Open Patent Application No. 60294/1981 is such that a conveying force toward the bound portion of a book is imparted by a roller to a sheet to be turned over to thereby form a loop. A wind is then applied to the loop or a bar-like member is inserted under the loop and the member is pivoted about the bound portion to thereby accomplish page turn-over. However, when a loop is to be made by a roller, it is necessary to stop the roller immediately after a loop of the first sheet has been formed, and control thereof has been difficult. Also, this apparatus requires a duct for the wind blast to be disposed and requires means for moving the bar-like member back and forth under the loop. This has led to the disadvantage that the entire apparatus becomes bulky.
The apparatus described in Japanese Laid-Open Patent Application No. 119125/1981 is such that a sheet to be turned over is held on a member by electrostatic attraction and the member is moved to thereby accomplish page turn-over. In such an apparatus, however, the member to which a voltage is applied must be moved while being insulated and the therefore, the structure for insulation becomes complex.
Also, when an opened book is placed on a flat bed, as in the above-described example of the prior art, the heights of the left and right uppermost sheets differ from each other except for when the thicknesses of the left and right groups of sheets with the bound portion of the book as the boundary are the same. If, in such a state, an attempt is made to photograph the spread left and right pages, the camera will be out of focus and blurred images will be formed.
Also, in the above-described example of the prior art, the direction in which pages are turned over has been limited to one direction and it has been impossible to turn over pages in the opposite direction.